Passing In Arguments

It is possible to pass information to a userform however you cannot use the Userform_Initalise event.
The Userform_Initailize event does not allow arguments to be passed to it.
There are a number of different ways you can work around this.
Which one you use will depend if you want to use the argument in the Initialise event.

Used in the Initialise - Global Variable

Global variable

Public DisplayUserForm() 
Dim oMyForm As UserForm1 
   Set oMyForm = New UserForm1 
   oMyForm.g_sCaptionTitle = "myvalue" 
   oMyForm.Show 
End Sub 

Public g_sCaptionTitle As String 

Used after Initialise - Userform Property

Creating a userform property is the best approach because it means that your code is self-contained (encapsulation principles)

Public DisplayUserForm() 
Dim oMyForm As UserForm1 
   Set oMyForm = New UserForm1 
   oMyForm.Property_CaptionTitle = "some text" 
   oMyForm.Show 
End Sub 

Private m_sCaptionTitle As String 
Property Let Property_CaptionTitle(ByVal sValue As String) 
   m_sCaptionTitle = sValue 
End Property 
Property Get Property_CaptionTitle() As String 
   Property_CaptionTitle = m_sCaptionTitle 
End Property 

Alternatives

Using Tag property